The present invention relates to a railroad car positioning device for use in moving one or more railroad cars along a track towards a railroad car dumping apparatus, and a method for positioning railroad cars for dumping. Such positioning devices are generally adapted to travel along tracks that are parallel to the railroad tracks upon which the railroad cars move and have an arm which may be coupled to one railroad car or simultaneously coupled to two spaced railraod cars, and move the car or cars into a position within the dumping apparatus.
Car positioning devices have been provided which may be used in connection with "unit train" type unloading where the cars remain coupled together during the dumping cycle, using rotary couplers on the cars, or with random railroad cars, where cars, or pairs of cars, are separated from adjacent cars during the dumping cycle. Devices have also been provided, for example, in U.S. Pat. No. 3,942,451, which are usable in connection with both a unit train and random car dumping cycle. In U.S. Pat. No. 3,942,451, a train positioner has an L-shaped positioner arm having "E" type couplers which can swing into position to extend in either direction from the arm so that the positioner can be used to push or pull cars in either direction along the tracks. The arm, however, cannot be extended far enough towards the dumper so as to directly position a car within the dumper for a dumping cycle. This requires that an additional car must be used to push the car to be dumped into position in the dumping apparatus. Also, although the couplers on the arm can be uncoupled automatically, a workman must uncouple the pusher car from the car to be dumped, thus requiring an additional workman.
In U.S. Pat. No. 3,169,490, a train positioner is described which is mounted on a transfer table. A hook on the end of an extended support, pivotally mounted on the positioner arm to extend in either direction, can be coupled to a car on a selected track to pull a car onto the table. This positioner is also suggested for use in positioning and removing cars from an unloader.
A need exists, however, for a train positioning device and car positioning method which, in addition to moving the car or cars towards a dumper, can directly position the cars in the dumper for the dumping cycle.